Placement of ureteric stents to address postoperative urinary leakage in calyceal diverticulum with partially duplicated ureters resembling a renal cyst: A case report.

Rationale: Renal pelvic diverticulum accounts for fewer than 5% of renal cystic lesions. Its coexistence with a duplicated renal system is exceedingly rare, posing significant diagnostic and therapeutic challenges. These cases require differentiation from typical renal cysts and often necessitate a unique management approach.

Patient Concerns: A 57-year-old woman was initially misdiagnosed with a simple renal cyst and underwent laparoscopic cyst unroofing and decompression. Postoperatively, she developed persistent urinary leakage. Further investigation revealed a renal pelvic diverticulum associated with ureteral duplication.

Diagnoses: Renal pelvic diverticulum combined with duplicated renal pelvis and ureter.

Interventions: The patient underwent bilateral retrograde ureteral stent placement via flexible ureteroscopy, along with the insertion of a transurethral indwelling catheter to facilitate urinary drainage.

Outcomes: At the 2-month follow-up, the patient was asymptomatic. Renal ultrasonography showed a 1 cm cystic lesion in the mid-pole of the right kidney without any perirenal fluid collection. Bilateral ureteral stents were successfully removed.

Lessons: This case highlights the importance of distinguishing renal pelvic diverticula from simple cysts using advanced imaging modalities and demonstrates an effective strategy for managing postoperative complications such as urinary leakage.